GAO ZHISHENG: Lawyer, in jail

Gao Zhisheng, a writer and self-taught lawyer, became known in China for defending citizens against the state.

His pro-bono work has included cases for evicted homeowners, human rights activists, victims of medical malpractice and members of the banned Falun Gong spiritual movement.

He published a book, A China More Just, detailing his experiences of confronting China's legal and political system.

In August 2006, Mr Gao was arrested for "inciting subversion" through his writing.

He was sentenced to three years in prison in December 2006 but the jail term was suspended for five years. Mr Gao says he was tortured on several occasions while in detention.

He was also reportedly the target of an assassination attempt.

He went missing in February 2009, reappeared briefly a year later to say he was giving up campaigning for the sake of his family, and went missing again in the western province of Xinjiang in April 2010.

In December 2011 state media reported that Mr Gao had been sent back to jail for three years, having "seriously violated probation rules".

His brother Gao Zhiyi was allowed to visit him at the Shaya County jail in Xinjiang's Aksu prefecture for 30 minutes in March.

Gao Zhiyi told journalists that he met Gao Zhisheng, but it was "not convenient" for him to elaborate further.

Mr Gao's wife and two children sought asylum in the United States in early 2009 and are now living in California.

BAO TONG: Former official, under house arrest

In the late 1980s, Bao Tong was one of the most powerful men in China, as adviser to the then-Communist Party chief Zhao Ziyang.

Both men opposed the brutal crackdown on students during the Tiananmen Square protests of 1989, and both suffered for their stance.

Within weeks, Mr Zhao was ousted and Mr Bao jailed for seven years.

He has been under house arrest since his release in 1997, but still managed to sign the Charter 08 manifesto and reportedly smuggle out audiotapes made by Mr Zhao to Hong Kong, where they formed the basis of a memoir published after his death.

SHI TAO: Journalist, in jail

Shi Tao, who worked for the Contemporary Business News in China, was jailed for 10 years in 2005 for "divulging state secrets" - a charge commonly used to prosecute dissidents and pro-democracy activists.

Mr Shi was jailed for sending on to foreign websites an e-mail from the ruling Communist Party warning journalists not to cover the 15th anniversary of the Tiananmen Square massacre in 2004.

His case has become a cause celebre for free speech campaigners - not least because internet firm Yahoo was accused of informing on him.

The US-based web giant passed on details of his whereabouts to the authorities, and has since apologised to Shi Tao's mother.

DING ZILIN: Activist, presumed house arrest

Ding Zilin's teenage son was shot in the back by soldiers during the 1989 Tiananmen Square protests.

Along with other bereaved parents, she formed a group called the Tiananmen Mothers, which has spent the past two decades pushing for a full account of what happened that night in Beijing.

The former philosophy professor and her husband are believed to be under house arrest.

Liu Xiaobo has said in the past that the Tiananmen Mothers should win the Nobel Peace Prize for their work.

QIN YONGMIN: China Democracy Party co-founder

Just days after completing a 12-year jail term for subversion, Qin Yongmin vowed to advance human rights and democracy in China.

Mr Qin was sentenced to prison in 1998 after he and other activists tried to officially register the China Democracy Party.

Previously, Mr Qin was jailed from 1981-1989 as a "counter-revolutionary" following China's "democracy wall" period of political openness.

In 1993, he was sentenced to two years in a labour camp for drafting the "Peace Charter," a manifesto that called for a re-evaluation of the 1989 Tiananmen protests and the release of political prisoners.

"As a democrat, this is my life. One day, the China Democracy Party will be legal in China, but this will take time," he said in a phone interview with AFP from his home in Wuhan.

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